METHOD FOR REDUCING THE RISK OF ROLLOVER OF AN AUTOMOTIVE VEHICLE PROVIDED WITH A CONTROLLABLE SUSPENSION SYSTEM

• US 20160046167A1
• Filed: 03/26/2014
• Published: 02/18/2016
• Est. Priority Date: 03/26/2013
• Status: Active Grant

• Current Assignee: Institut national de recherche pour l'agriculture, l'alimentation et l'environnement, Universite Blaise Pascal - Clermont II
• Original Assignee: Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture, Université Blaise Pascal Clermont II
• Inventors: LENAIN, Roland, BOUTON, Nicolas, RICHIER, Mathieu, DIEUMET, Denis, THUILOT, Benoit
• Granted Patent: US 9,849,747 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60G 17/016 characterised by their responsiveness, when the vehicle is travelling, to specific motion, a specific condition, or driver input B60G17/017 takes precedence
• CPC Class Codes: B60G 17/0162 mainly during a motion involving steering operation, e.g. cornering, overtaking B60G17/0164 takes precedence
• CPC Class Codes: B60G 2300/08 Agricultural vehicles
• CPC Class Codes: B60G 2400/0521 Roll rate
• CPC Class Codes: B60G 2400/0522 Pitch rate
• CPC Class Codes: B60G 2400/0523 Yaw rate
• CPC Class Codes: B60G 2400/60 Load
• CPC Class Codes: B60G 2400/63 Location of the center of gravity
• CPC Class Codes: B60G 2800/0124 Roll-over conditions
• CPC Class Codes: B60G 2800/70 Estimating or calculating vehicle parameters or state variables
• CPC Class Codes: B60G 2800/9124 Roll-over protection systems, e.g. for warning or control

Abstract

A method for reducing the rollover risk of an automotive vehicle includes:

• • a first step of calculating, on the basis of a plurality of signals delivered by sensors (28, 29) of the controllable suspension system, a measured quantity (TCm) as an active value (TC) of a load transfer;
  • a second step of calculating an estimated quantity (TCe), on the basis of signals delivered by kinematic sensors (50-58) placed onboard the vehicle and a dynamic model of the vehicle, the estimated quantity being taken as an active value of the load transfer when the measured quantity is not available;
  • a step of evaluating the rollover risk on the basis of the active value (TC) of the load transfer; and, in the event of increased rollover risk; and
  • a step of the emission of a safety signal (S).

Claims

1. A method for reducing the rollover risk of an automotive vehicle (10) including a controllable suspension system (24-27), which comprises:

a first step of calculating, on the basis of a plurality of signals delivered by sensors (28, 29) of the controllable suspension system, a measured quantity (TCm) as an active value (TC) of a load transfer;

a second step of calculating an estimated quantity (TCe), on the basis of signals delivered by kinematic sensors (50-58) placed onboard the vehicle (10) and a dynamic model (M) of the vehicle, said estimated quantity being taken as an active value of the load transfer when the measured quantity is not available;

a step of evaluating the rollover risk on the basis of the active value (TC) of the load transfer; and

, in the event of increased rollover risk, and

a step of the emission of a safety signal (S).

2. The method according to claim 1, wherein, when the measured quantity (TCm) is available, the method includes a step for recalibrating at least one parameter (H, G) of the dynamic model (M) of the vehicle used in the second calculation step, said recalibration step consisting of:

evaluating a deviation between the measured quantity (TCm) and the estimated quantity (TCe); and

, when said deviation exceeds a threshold value (e0),

developing a law of evolution over time of said parameter, said law tending to reduce the deviation; and

, when the measured quantity (TCm) is available,

modifying, upon each iteration of the second calculation step, the parameter of the dynamic model of the vehicle by using the variation law.

3. The method according to claim 2, wherein said at least one parameter of the dynamic model (M) of the vehicle (10) is the mass (G) or the height of the center of gravity (H).

4. The method according to claim 3, wherein the time evaluation law for the height H of the center of gravity is given by a relationship of the type:

5. The method according to claim 4, wherein, the dynamic model (M) of the vehicle (10) including two parameters, i.e., the mass (G) and the height of the center of gravity (H), the method includes a step for weighting the time evolution laws of each of those two parameters using a coefficient resulting from a likelihood calculation of the cause of the need for recalibration.

6. The method according to claim 1, wherein, the controllable suspension system including active suspensions, the measured quantity (TCm) is calculated from signals representative of a force generated by each of the active suspensions (24-27).

7. The method according to claim 1, wherein the estimated quantity (TCe) is calculated from the following signals:

a longitudinal speed, delivered by a Doppler radar (50);

a longitudinal incline angle and a transverse incline angle of the vehicle, delivered by two inclinometers (52, 54);

an instantaneous speed of rotation relative to a vertical axis, delivered by an inertial unit (56); and

for each wheel, a turning angle, delivered by a wheel angle sensor (58).

8. The method according to claim 1, wherein the recalibration step makes it possible to indirectly estimate the instantaneous mass (G(t)) of said vehicle.

9. The method according to claim 1, wherein the safety signal (S) is taken into account in an actuating step of a controllable attitude correction system, so as to avoid rollover of the vehicle.

10. The method according to claim 1, wherein the safety signal (S) is taken into account in a step for regulating the propulsion and/or steering means of the vehicle, so as to prevent rollover of the vehicle.

11. An information recording medium, which includes instructions for carrying out a method for reducing the rollover risk of an automotive vehicle including a controllable suspension system, according to claim 1, when the instructions are executed by an electronic computer (30).

12. A system for reducing the rollover risk of an automotive vehicle (10) including a controllable suspension system (24-27), including an onboard computer (30), wherein the onboard computer is programmed to execute a method according to claim 1.

13. The system according to claim 12, including:

a Doppler radar (50) able to deliver a longitudinal speed;

two inclinometers (52, 54) able to deliver a longitudinal incline angle and a transverse incline angle of the vehicle;

an inertial unit (56) able to deliver an instantaneous speed of rotation relative to a vertical axis; and

for each wheel, a wheel sensor (58) able to deliver a turning angle.

14. An automotive vehicle including a controllable suspension system, wherein the vehicle has an onboard system for reducing the rollover risk according to claim 12.

15. The vehicle according to claim 14, wherein said safety signal (S) generated at the output of the system is taken into account by an actuating module (210) of the controllable suspension system and/or a regulating module (220) of the propulsion and/or steering means of the vehicle, to avoid rollover of the vehicle.